As it is known, mechanical transmissions are cooled and/or lubricated with lubricant-refrigerant oils, so as to increase their duration and obtain, at the same time, reliability even in the case of particularly high transmitted powers.
Furthermore, as it is known, a part of the lubricant oil inevitably leaks out in an axial direction through the teeth and flows outwards as a result of a centrifugal effect. Therefore, in use, a flow of drawn oil is formed, which must be collected and led to the tank, not only to avoid fluid leaks and high managing costs, but also to prevent said drawn oil from becoming, in turn, a source of additional leaks caused by the drawn oil hitting the rotary elements of the transmission.
To this aim, it is known to use external collectors to collect and channel the drawn oil; the oil collected in said external collectors is quickly led towards the oil suction area, filtered and reintroduced in the system.
Known collection collectors, despite being able to partly fulfil the main function of collecting the drawn oil, have proven to be not good enough for the following reasons.
First of all, current collection collectors cannot avoid the formation of splashes and the return of the drawn oil towards the rotary elements and, in general, they are not able to limit fluid-dynamic leaks due to the drawn oil hitting the rotary organs.
In addition, known collection collectors are generally sized taking into account the nominal operating conditions of the transmission. For this reason, known collection collectors turn out to be ineffective when the transmission operates in so-called “off-design” conditions, namely with a rotation speed that is smaller than the nominal or normal operating rotation speed.
Finally, known collection collectors often require strict tolerances and clearances in the coupling with rotary parts that complicate both their manufacturing process and their assembly, often because of the need to provide mechanical seals to intercept oil splashes.